pH drop?

[Michaels Mom]

The first time we tested the pH in our tank it was between 7.7 and 8.0. Every reading since has been 8.0. Tonight it was back to 7.7-8.0 again. Any idea what would cause it to drop? Amonia, Nitrite, Nitrate all unchanged at 0. Our salinity is down a bit from 1.0262 to 1.0252. I think that's because we switched from mostly purchased water to mixing our own (with RO water). Would that have an effect on the pH? Should I be concerned?

We're on the tail end of an algae bloom and our protein skimmer is finally happily bubbling away. Changed our pumps around and added a wavemaker. Again, could this cause a problem? Everyone seems happy, but I don't like unexplained changes.

Thanks in advance!

[da1jewfish]

I'm guessin ur still cycling ur tank? and u do have fish? what size tank?

If u have fish in there u need to keep a close eye, and test every few hours or so. 7.7 to 8.0pH over a little time isn't a big jump but if it happens all the time its a problem and over short periods, not good.

Test that RO water its probably low pH... the salt mix will buffer that though if you give it time.
Goodluck

[dorkfish]

Can you test the water in the AM? If you read the reefkeepers FAQ, you will read something about fuluctauting PH in reef tanks between the AM and PM, and that it's nothing to be woried about.

[dorkfish]

Test that RO water its probably low pH... the salt mix will buffer that though if you give it time.
Good luck
The RO may have a low PH, but it also has low buffering capacity, so any good salt mix that is worth buying should be able to adjust RO water to the correct, or atleast close to corect PH.

[Michaels Mom]

My husband works late at night so early morning usually isn't an option. I'll see what I can do this weekend. If you're concerned that it's just a time of day fluctuation, we generally end up doing maintenance between 9 and 11pm, very consistently. It's hard to get anything done with a 4 year old trying to help!

This is a link to the water that we use: http://www.drinkmorewater.com/technology/analysis/

We use instant ocean salt

As far as stocking we have 2 small clownfish, 1 lawnmower blenny that I haven't seen in a couple days. He's been hiding ever since we added the wavemaker tuesday night. I figured we'd give him til the weekend's over before going looking for him? Also have a blue star, 6 hermit crabs, 3 conch snails (small) and 3 large turbo snails.

I've never really understood the cycling the tank thing. When we purchased the set up it had been live rock only for about 5 months, then we let is set up for a couple weeks before adding anyone. Other than a small spike in nitrates when we first added the fish, our numbers have been remarkably consistent.

Can anyone recommend a good place to get water testing kits? We've been testing for salinity, pH, amonia, nitrite, nitrate, and hardness. I'd like to test for phosphates as well. Anything else we're missing?

[mogurnda]

Two possibilities. One is that you have increased amounts of dissolved CO2, which acidifies the water. It would either come from too little circulation in the tank, or a room with high levels of CO2. Seems unlikely, unless you have suddenly closed all the windows and doors. Plus you recently increased the circulation, if I understand correctly.

The other possibility is that your buffers, which maintain you pH, have been depleted. This can happen if you have coral growth without supplementing carbonate, or if organic acids (from fish waste or uneaten food) are neutralizing your buffers. What is your alkalinity right now?

I order all my kits from www.premiumaquatics.com. Salifert's my favorite for most, because they are reliable, relatively simple, and easy to read. Unless I am cycling a tank, I generally only measure alkalinity and calcium, occasionally checking nitrate and phosphate to be sure they are OK.

[Michaels Mom]

Thanks for all your help, I really appreciate it!!! Are alkalinity and hardness the same thing? If so, we're pretty consistent at 8.5. We'll definitely add some buffer tonight. Especially since I just found out we have some coraline algae starting to grow.

We just added extra water flow and are going to play with it even more when we get some more loc-line in.

Just did a phosphate test and it came out either at 0 or .25. I'm leaning more toward 0. We kept the lights off all day today and will replace the bulbs tonight. Hopefully that will finish off the algae. I'll repeat the pH test tomorrow.

Does all this sound like a decent plan?

[mogurnda]

Are alkalinity and hardness the same thing?More or less. I tend to think of hardness as a FW measure, but you can take kH and divide it by 2.8 and get alkalinity. So you have an alk of about 3, which is fine. I wouldn't add too much more buffer.

One easy test of whether you have excess CO2 is to take a sample of water, bubble it vigorously (in a room that you know is well-ventilated) for 15-30 minutes and retest the pH. If it goes up, there is CO2 buildup in the tank.